<template>
	<div class="icon-selector">
		<el-popover placement="bottom" :width="state.fontIconWidth" v-model:visible="state.fontIconVisible" popper-class="icon-selector-popper">
			<template #reference>
				<el-input
					v-model="state.fontIconSearch"
					:placeholder="state.fontIconPlaceholder"
					:clearable="clearable"
					:disabled="disabled"
					:size="size"
					ref="inputWidthRef"
					@clear="onClearFontIcon"
					@focus="onIconFocus"
					@blur="onIconBlur"
				>
					<template #prepend>
						<SvgIcon
							:name="state.fontIconPrefix === '' ? prepend : state.fontIconPrefix"
							class="font14"
							v-if="state.fontIconPrefix === '' ? prepend?.indexOf('element') > -1 : state.fontIconPrefix?.indexOf('element') > -1"
						/>
						<i v-else :class="state.fontIconPrefix === '' ? prepend : state.fontIconPrefix" class="font14"></i>
					</template>
				</el-input>
			</template>
			<transition name="el-zoom-in-top">
				<div class="icon-selector-warp" v-show="state.fontIconVisible">
					<div class="icon-selector-warp-title flex">
						<div class="flex-auto">{{ title }}</div>
						<div class="icon-selector-warp-title-tab" v-if="type === 'all'">
							<span :class="{ 'span-active': state.fontIconType === 'ali' }" @click="onIconChange('ali')" class="ml10" title="iconfont 图标"
								>ali</span
							>
							<span :class="{ 'span-active': state.fontIconType === 'ele' }" @click="onIconChange('ele')" class="ml10" title="elementPlus 图标"
								>ele</span
							>
							<span :class="{ 'span-active': state.fontIconType === 'awe' }" @click="onIconChange('awe')" class="ml10" title="fontawesome 图标"
								>awe</span
							>
						</div>
					</div>
					<div class="icon-selector-warp-row">
						<el-scrollbar ref="selectorScrollbarRef">
							<el-row :gutter="10" v-if="fontIconSheetsFilterList.length > 0">
								<el-col :xs="6" :sm="4" :md="4" :lg="4" :xl="4" @click="onColClick(v)" v-for="(v, k) in fontIconSheetsFilterList" :key="k">
									<div class="icon-selector-warp-item" :class="{ 'icon-selector-active': state.fontIconPrefix === v }">
										<div class="flex-margin">
											<div class="icon-selector-warp-item-value">
												<SvgIcon :name="v" />
											</div>
										</div>
									</div>
								</el-col>
							</el-row>
							<el-empty :image-size="100" v-if="fontIconSheetsFilterList.length <= 0" :description="emptyDescription"></el-empty>
						</el-scrollbar>
					</div>
				</div>
			</transition>
		</el-popover>
	</div>
</template>

<script setup name="iconSelector">
import initIconfont from '@/utils/getStyleSheets';

// 传值 setup="props"
const props = defineProps({
	// 输入框前置内容
	prepend: {
		type: String,
		default: () => 'elementPointer',
	},
	// 输入框占位文本
	placeholder: {
		type: String,
		default: () => '请输入内容搜索图标或者选择图标',
	},
	// 输入框占位文本
	size: {
		type: String,
		default: () => 'small',
	},
	// 弹窗标题
	title: {
		type: String,
		default: () => '请选择图标',
	},
	// icon 图标类型
	type: {
		type: String,
		default: () => 'ele',
	},
	// 禁用
	disabled: {
		type: Boolean,
		default: () => false,
	},
	// 是否可清空
	clearable: {
		type: Boolean,
		default: () => true,
	},
	// 自定义空状态描述文字
	emptyDescription: {
		type: String,
		default: () => '无相关图标',
	},
	// 双向绑定值，字段名为固定，改了之后将不生效
	// 参考：https://v3.cn.vuejs.org/guide/migration/v-model.html#%E8%BF%81%E7%A7%BB%E7%AD%96%E7%95%A5
	modelValue: String,
});

// 事件
const emit = defineEmits(['update:modelValue', 'get', 'clear']);

const inputWidthRef = ref();
const selectorScrollbarRef = ref();
const state = reactive({
	fontIconPrefix: '',
	fontIconVisible: false,
	fontIconWidth: 0,
	fontIconSearch: '',
	fontIconSheetsList: [],
	fontIconPlaceholder: '',
	fontIconType: 'ali',
});

// 处理 input 获取焦点时，modelValue 有值时，改变 input 的 placeholder 值
const onIconFocus = () => {
	if (!props.modelValue) return false;
	state.fontIconSearch = '';
	state.fontIconPlaceholder = props.modelValue;
};

// 处理 input 失去焦点时，为空将清空 input 值，为点击选中图标时，将取原先值
const onIconBlur = () => {
	setTimeout(() => {
		const icon = state.fontIconSheetsList.filter((icon) => icon === state.fontIconSearch);
		if (icon.length <= 0) state.fontIconSearch = '';
	}, 300);
};

// 处理 icon 双向绑定数值回显
const initModeValueEcho = () => {
	if (props.modelValue === '') return false;
	state.fontIconPlaceholder = props.modelValue;
	state.fontIconPrefix = props.modelValue;
};

// 图标搜索及图标数据显示
const fontIconSheetsFilterList = computed(() => {
	if (!state.fontIconSearch) return state.fontIconSheetsList;
	let search = state.fontIconSearch.trim().toLowerCase();
	return state.fontIconSheetsList.filter((item) => {
		if (item.toLowerCase().indexOf(search) !== -1) return item;
	});
});

// 获取 input 的宽度
const getInputWidth = () => {
	nextTick(() => {
		state.fontIconWidth = inputWidthRef.value.$el.offsetWidth;
	});
};

// 监听页面宽度改变
const initResize = () => {
	window.addEventListener('resize', () => {
		getInputWidth();
	});
};

// 初始化数据
const initFontIconData = async (type) => {
	state.fontIconSheetsList = [];
	if (type === 'ali') {
		await initIconfont.ali().then((res) => {
			// 阿里字体图标使用 `iconfont xxx`
			state.fontIconSheetsList = res.map((i) => `iconfont ${i}`);
		});
	} else if (type === 'ele') {
		await initIconfont.ele().then((res) => {
			state.fontIconSheetsList = res;
		});
	} else if (type === 'awe') {
		await initIconfont.awe().then((res) => {
			// fontawesome字体图标使用 `fa xxx`
			state.fontIconSheetsList = res.map((i) => `fa ${i}`);
		});
	}
	// 初始化 input 的 placeholder
	// 参考（单项数据流）：https://cn.vuejs.org/v2/guide/components-props.html?#%E5%8D%95%E5%90%91%E6%95%B0%E6%8D%AE%E6%B5%81
	state.fontIconPlaceholder = props.placeholder;
	// 初始化双向绑定回显
	initModeValueEcho();
	// 切换时，滚动条置顶。感兴趣可以使用 keep-alive <component :is="xxx"/> 进行缓存
	selectorScrollbarRef.value.wrap$.scrollTop = 0;
};

// 图标点击切换
const onIconChange = (type) => {
	state.fontIconType = type;
	initFontIconData(type);
};

// 获取当前点击的 icon 图标
const onColClick = (v) => {
	state.fontIconPlaceholder = v;
	state.fontIconVisible = false;
	state.fontIconPrefix = v;
	emit('get', state.fontIconPrefix);
	emit('update:modelValue', state.fontIconPrefix);
};

// 清空当前点击的 icon 图标
const onClearFontIcon = () => {
	state.fontIconPrefix = '';
	emit('clear', state.fontIconPrefix);
	emit('update:modelValue', state.fontIconPrefix);
};

// 页面加载时
onMounted(() => {
	// 判断默认进来是什么类型图标，进行 tab 回显
	if (props.type === 'all') {
		if (props.modelValue?.indexOf('iconfont') > -1) onIconChange('ali');
		else if (props.modelValue?.indexOf('element') > -1) onIconChange('ele');
		else if (props.modelValue?.indexOf('fa') > -1) onIconChange('awe');
		else onIconChange('ali');
	} else {
		onIconChange(props.type);
	}
	initResize();
	getInputWidth();
});

// 监听双向绑定 modelValue 的变化
watch(
	() => props.modelValue,
	() => {
		initModeValueEcho();
	}
);
</script>
